1. Field of the Invention
The present invention relates to an image forming apparatus, such as a copying machine or a printer, and, in particular, to an image forming apparatus in which the interior of the main body of the apparatus is cooled by a cooling fan.
2. Related Art
FIG. 6 is a sectional view of a conventional image forming apparatus. In the drawing, symbol P indicates a sheet of paper, numeral 101 indicates an image fixing apparatus, numeral 102 indicates a laser scanner, numeral 103 indicates a sheet discharge outlet, numeral 104 indicates an intake fan, numeral 105 indicates a sheet feeding tray, numeral 106 indicates a sheet feeding roller, numeral 107 indicates a photosensitive drum, numeral 108 indicates a toner cartridge, and numeral 110 indicates a sheet feeding tray.
FIG. 7 is a plan view of the image forming apparatus shown in FIG. 6. In the drawing, numeral 109 indicates an air outlet. The other components are indicated by the same reference numerals as those in FIG. 6.
Next, the operation of this image forming apparatus, constructed as described above, will be illustrated.
When a printing command from a host computer (not shown) is received, the sheet P is fed by the sheet feeding roller 106. At the same time, a latent image formed on the photosensitive drum 107 by the laser scanner 102 and borne on the photosensitive drum is developed in the toner cartridge 108 and visualized as a toner image. Then, the toner image is transferred to the sheet P. The toner image thus transferred is fixed to the sheet P by the image fixing apparatus 101, and then the sheet P is discharged from the sheet discharge outlet 103.
It is to be noted that heat is generated from the image fixing apparatus 101, the laser scanner 102, etc., and this heat causes a temperature rise in various portions of the main body. In view of this, air is taken in from the exterior of the apparatus by the intake fan 104, and the interior of the apparatus is cooled by this air. The air that has been warmed as a result of the cooling is discharged from the air outlet 109, whereby the temperature of the various portions of the apparatus is kept at a level not higher than a constant value.
However, in the above conventional image forming apparatus, in which a cooling fan is mounted to a side of the apparatus main body, the cooling of the apparatus is effected from the width direction that is perpendicular to the direction in which the sheet is conveyed. As a result, the apparatus to be cooled involves generation of a difference in temperature in the width direction.
When a plurality of apparatuses are to be cooled, it is necessary to distribute the air by, for example, providing a plurality of cooling fans or providing a duct.
Further, when the air that has cooled the image fixing apparatus is discharged through, for example, a side portion of the apparatus main body, steam which has been generated from the sheet heated by the image fixing apparatus is also discharged, with the result that the sheet conveyance passage from the image fixing apparatus onward is dried, thereby causing the sheet to be curled.
It is an object of the present invention to provide an image forming apparatus which allows a plurality of apparatuses to be cooled uniformly in the width direction without having to use any special member.
Another object of the present invention is to provide an image forming apparatus which has an image forming means for forming an image on a moving recording material and a fan for taking in air from the exterior of the apparatus to cool the interior thereof, wherein the fan is arranged so as to be inclined with respect to the direction in which the recording material moves.
Further objects of the present invention will become apparent from the following description.